Infants sleeping on their side may affect the shape of their face, while adults sleeping on their side usually do not affect the shape of their face. Infants’ head shape is not yet completely set, the bones are highly plastic, if the infant sleeps on the side for a long time, it may affect the shape of the face, resulting in the face shape of one side is big and the other side is small, so parents try not to let the infant sleep on the side. Adults’ facial bones have been fully developed, the head shape is completely stereotyped, and the bones of adults are relatively hard, even if they sleep on their side for a long time, the effect on the face shape is not big, basically negligible. However, whether adults or infants, are not recommended to sleep on the side for a long time, to avoid the pressure on one side of the limbs, it is recommended to regularly change the sleeping position.